Articles & Case Studies

LATEST MILESTONE REACHED ON UNITED UTILITIES’ PIPELINE SCHEME

Posted: Monday 11th October 2010

J Murphy & Sons Limited has commenced one of the longest tunnelling drives as part of the £125 million West East Link Main (WELM) pipeline scheme for United Utilities.

Using micro tunnelling techniques, Murphy kicked off the 650m drive underneath the Metrolink line near Bury, which will link Hollinhurst Road with Springwater Park at the top end of the pipeline route. Around 10km of the pipeline route passes through Bury, including tunnels under the River Roch and the East Lancashire Railway.

WELM is one of the most ambitious water pipeline projects undertaken in the United Kingdom. As the main contractor, Murphy is building the 54.5km 1200mm diameter welded steel pipeline to enable the transportation of potable water bi-directionally from Prescot Reservoir near Liverpool, to Woodgate Hill Reservoir in Bury, Greater Manchester. Once complete in 2011 it will be able to move 100 million litres of water a day between the two conurbations.

The scheme presents many engineering challenges along the route due to the sheer scale of the project, varying ground conditions, previous mining working, ecological issues, the terrain, traffic management and the timescales required to complete the project.

The 44 crossings along the pipeline route include the M6, M61, M66, the A580 at three locations, major rivers and six railway lines. The initial design included 15 tunnels, but United Utilities has since increased the number to 27, to further minimise disruption to transport routes and woodland. In total there is now 5.2km of tunnels on the scheme.

Murphy project director, Maurice Corridan, says: “In a standard pipeline scheme you may get one or two tunnel sections, but to have 15, which are then increased to 27 tunnels along the route, is quite a challenge.

“This will take the construction phase of the scheme up to November this year, with pipeline testing and commissioning going into 2011. More than 25km of the 54.5km pipeline installed has already been tested.

“At its peak the scheme had 450 construction personnel working on site. We’ve now scaled this down slightly to 380 personnel with six mainline pipe crews, two auger boring crews and 3 tunnelling crews currently out on site.”

Jon Higham, senior project manager for United Utilities, added: “The WELM scheme is a fantastic feat of engineering, planning and project management, which takes in more than 200 landowners and tenants, five golf courses and eight separate Borough Councils.

“When complete it will help to help safeguard supply for our seven million customers, and provide more flexibility in the future in times of drought or to allow maintenance on our other major pipelines in the region.”